Bethlehem, West Bank (CNN) - Pope Francis extended an invitation Sunday to the leaders of Israel and the Palestinian Authority to travel to the Vatican for a "peace initiative," after earlier calling for a two-state solution to the intractable conflict.

The pontiff's remarks came at the end of an outdoor Mass in Bethlehem's Manger Square on the second day of his three-day trip to the Middle East.

"In this, the birthplace of the Prince of Peace, I wish to invite you, President Mahmoud Abbas, together with Israeli President Shimon Peres, to join me in heartfelt prayer to God for the gift of peace," Francis said.

"I offer my home in the Vatican as a place for this encounter of prayer."

He added, "Building peace is difficult, but living without peace is a constant torment. The men and women of these lands, and of the entire world, all of them, ask us to bring before God their fervent hopes for peace."

The Palestinian side has accepted the invitation and Palestinian Authority President Mahmoud Abbas will go to the Vatican, a Palestinian Legislative Council member, Hanan Ashrawi, told CNN.

The Israeli President's office said that he welcomed the invitation. "President Peres has always supported, and will continue to support, any attempts to progress the cause of peace," his office said.

It might sound like the start of a trite joke, but it’s actually the entourage for one of the most highly anticipated papal trips in recent history.

As Pope Francis heads to Jordan, Bethlehem and Jerusalem this weekend, he’s bringing along two old friends from Argentina: Rabbi Abraham Skorka, who co-wrote a book with the Pope, and Sheikh Omar Abboud, who leads Argentina’s Muslim community.

The Vatican says it’s the first time that a pope’s official entourage has included interfaith leaders.

In a region roiled by competing religious and political visions, Francis’ chosen companions communicate an unmistakable message, church officials said.

“It’s highly symbolic, of course,” said the Rev. Thomas Rosica, a consultant to the Vatican press office.

“But it also sends a pragmatic message to Muslims, Christians and Jews that it’s possible to work together - not as a system of checks and balances but as friends.”

The visit to the Holy Land is the first for Francis as leader of the Roman Catholic Church, and just the fourth for any pontiff in the modern era.

With so much at stake - the stalled negotiations between Israelis and Palestinians, the plight of Christian refugees - the Pope’s every word, gesture and photo-op will be microscopically examined.

Already, some conservative Israelis are advocating against the Pope’s visit, scrawling anti-Christian graffiti on Catholic buildings in Jerusalem and planning protests outside papal events in Jerusalem.

While the protesters form a fringe minority, they underscore the tensions that simmer around the Pope’s short but substantial trip.

With those challenges in mind, here are five key things to pay particular attention to.

(CNN) - A Harvard club's plans to stage a satanic "black Mass" were abruptly cancelled Monday after drawing fire from the Archdiocese of Boston and condemnation from the president of the Ivy League school.

Lucien Greaves, a spokesman for the New York-based Satanic Temple, told the Boston Globe late Monday that the event was called off because no venue was available.

“Everyone involved, outside of the Satanic Temple, got really scared,” Greaves told the newspaper. “And I don’t necessarily blame them, because I understand that they were getting a lot of vitriolic hate mail, and I don’t think they expected it."

Greaves was not immediately available for further comment.

A petition to stop the black Mass had garnered 60,000 signatures, according to Aurora Griffin, president of the Harvard Student Catholic Association.

The Harvard Extension Cultural Studies Club had planned host the two-hour ceremony at the Queens Head pub in Memorial Hall in on the school's campus in Cambridge, Massachusetts. It is unclear why the building was no longer available.

The history of black Masses is murky, but Catholics say the intent of such ceremonies is obvious: to mock their rituals and beliefs. The Masses often parody Catholic sacraments, such as Communion, and liturgical vestments.

“Our purpose is not to denigrate any religion or faith, which would be repugnant to our educational purposes," the Harvard student group had said in a statement, "but instead to learn and experience the history of different cultural practices.”

The cultural club said it also plans to host a Shinto tea ceremony, a Shaker exhibit and a presentation on Buddhist meditation.

But Harvard University President Drew Faust called the plans to reenact a black Mass "abhorrent."

(CNN) - When the news broke the other day that Philip Seymour Hoffman would receive a Catholic funeral on Friday, a few people on social media expressed surprise.

One commenter on my Facebook page questioned whether it was appropriate for the church to provide a high-profile Catholic funeral to someone whom she described as "a public sinner."

As you probably know, Hoffman, one of this generation’s most celebrated actors, died last weekend of an apparent heroin overdose.

The Facebook critic recanted her comment when I explained that the funeral will not be high-profile. Instead, the Hoffman family is holding a private ceremony Friday at St. Ignatius Loyola Church in New York.

Although Hoffman was nominated for Oscars twice for playing religious figures - a Catholic priest in “Doubt” in 2009, a cult leader in “The Master" in 2012 - his own faith wasn’t widely known.

(CNN) - Amid the iconic art in the Sistine Chapel on Sunday, Pope Francis told mothers that it's acceptable to breastfeed their children in public, even in holy sites like churches.

Children's voices, even when crying, make "the most beautiful choir of all," Francis said during a service in which he baptized 32 children.

"Some will cry because they are uncomfortable or because they are hungry," the Pope said. "If they are hungry, mothers, let them eat, no worries, because here, they are the main focus."

The Sistine Chapel, with its famous frescoes by Michelangelo, is the official chapel of the Apostolic Palace, traditionally the papal residence. Francis, though, lives in the Vatican guesthouse, Casa Santa Marta, saying it better suits his low-key style.

The Pope's remarks echo statements he made to an Italian newspaper in December in which he tied breastfeeding to the problem of global hunger.

(CNN)- When John F. Kennedy was a boy, his mother counseled her children on Good Fridays to pray for a peaceful death.

Young Jack joked that he’d rather pray for two pet dogs.

If you’re looking for the CliffsNotes version of Kennedy’s Catholicism, that anecdote touches on the key themes: the pious Irish mother, the light-hearted irreverence, the ever-present prospect of death.

But there’s much more to the story.

In the words of one biographer, Kennedy was Mr. Saturday Night but also Mr. Sunday Morning, rarely missing a Mass.

He was famously unfaithful to his wife but fiercely loyal to his church, even when it threatened his quest for the presidency.

One scholar suggests that Kennedy was becoming more religious as the Cold War wore on. Another says that Kennedy’s public displays of piety were little more than political lip service.

As the country marks the 50th anniversary of Kennedy’s death- and it was far from peaceful, as we all know - almost every aspect of his life is again under the media microscope. But for all the ballyhoo about Kennedy being the first and only Catholic president, the topic of his faith remains largely untouched.

(CNN) - After morning Mass on most Saturdays, you’d find the Rev. Dan Atkins cutting into a thick stack of pancakes or digging into a plate of eggs. But this Saturday’s menu is a bit spartan.

“I’ll probably just have coffee and a piece of toast,” said Atkins, the pastor of Holy Family Catholic Church in New Albany, Indiana.

The Catholic priest isn’t on a diet. Rather, he’s one of many believers across the country - and throughout the world - heeding the call of Pope Francis to fast and pray for peace in Syria on Saturday.

“It’s a way to be in solidarity with people who are suffering terribly from war,” said Atkins, a native of southern Indiana. “I’m going to be thinking about the children, the kids, affected by this terrible conflict.”

Washington (CNN)–With the goal of urging the House to pass a comprehensive immigration reform bill, the Catholic Church is organizing a targeted effort to push immigration reform in the pews and target Catholic lawmakers – particularly Republicans – who may be on the fence over the politically tenuous bill.

The movement, which was first reported in The New York Times, will include coordinated immigration reform sermons on September 8, as well as targeted messaging of Catholic lawmakers, including House Speaker John Boehner and Rep. Paul Ryan, the GOP’s 2012 vice presidential candidate.

RIO DE JANEIRO (CNN) - With a blasting medley of bossa nova music as a prelude, Pope Francis addressed about a million worshippers in Copacabana beach on Thursday, lacing his message to a new generation of Catholics with Brazilian street jargon.

"Bota Fe" - put on faith - was the antidote to what he called growing materialism and discontent, the pontiff said.

"What can we do? Bota Fe," he said. "If we want to have real meaning and fulfillment, as you want and you deserve ... put on faith."

The thread of the pontiff's speech resonated with Brazil's youth, many of whom are expressing disenchantment with their government.

Rome (CNN) - Crowds lined the walls and spilled out the front door of the Church of Our Lady of Guadalupe on Monte Mario on Sunday to catch a glimpse of the gregarious American Cardinal Timothy Dolan, archbishop of New York, who smiled broadly as he came into the church, stopping to wave to photographers and kiss a baby whose parents were holding him up.

Dolan has made the short lists of some Vatican watchers as a likely choice to be elected as the next pope by the College of Cardinals, a designation called "papabili" in Italian.

A local officiant began the service by saying it was great to have Dolan at the church close to Easter.

The CNN Belief Blog covers the faith angles of the day's biggest stories, from breaking news to politics to entertainment, fostering a global conversation about the role of religion and belief in readers' lives. It's edited by CNN's Daniel Burke with contributions from Eric Marrapodi and CNN's worldwide news gathering team.